The present invention relates to an integrated circuit device, and, more particularly, to an integrated circuit device having a simplified bias supply circuit for supplying bias power sources for a plurality of circuit units.
In a logic circuit and the like composed of, for example, ECL (emitter coupled logic) circuits, it is necessary to supply a plurality of bias voltages to the constant current source circuits of each logic circuit and to the logic transistor thereof. Therefore, in an integrated circuit device having a large number of such logic circuits, the scale of a bias circuit supplying bias voltages to each logic circuit becomes relatively large, leading to a greater power consumption by the bias circuit itself. To remove these drawbacks, it is necessary to redivise the circuit structure of the bias circuit.
In a conventional integrated circuit device a plurality of bias supply portions are provided, each supplying bias voltages to a corresponding one of a plurality of logic portions. However, such a circuit device is disadvantaged in that the internal circuit of each bias supply portion itself becomes complex, leading to a corresponding increase in the power consumption thereof because each of the bias supply portions must be a stabilized bias voltage generating circuit.
In another conventional integrated circuit device, one common bias circuit and a plurality of inner bias circuits are provided, each of which corresponds to one of a plurality of logic circuit portions. The common bias circuit supplies stabilized bias voltages to each of the logic circuit portions, and each of the inner bias circuits generates and supplies inner bias voltages to the corresponding logic circuit portions.
However, in the above-mentioned integrated circuit device, it is necessary to provide two connection lines between the common bias circuit and each of the inner bias circuits. This means that a large number of connection lines must be used in the bias portion, which reduces the reliability and lowers the degree of integration of the integrated circuit device.